Mine



C. N. HICKMAN MINE Filed May 17, 1924 2 Sheets-Sheet l June 30, 1925. 1,543,920

C. N. HICKMAN MINE Filed may 17, 1924 2 sheets-sheet Patented .lune 30, 1925.

rss2' MINE; l

Application led May 17j 19245. Serial No. 714,099;

To all' whom tmay concern.'

Beit known that l, @Lannnon N. Hiern- MAN, a citizen off' the nitedi States, residiing at New York, New York, hare invented new and useful Improvements in Mines, off which the following" is ai specification;

This invention relates to improvements in mines and: more particularly toY that class of submarine mines lino-wn as ballast or drifting mines.

Als isl well known to those familiar with the tactical use of inventionsi of this cha-r'- acter, it is' frequently desirable to discharge from' a pursued vessel, for example, a plusv ra'lity of mines which ilo at in its wa-heA thereby to beA engaged by the pursuing vessel to the damage or destruction ofthe latter.

These mines are not anchored in anyway but drift freely for a predetermined time and. it is desirableof course, that they oc,- cupy a position well'below the surface ofthe water where their detection by the pursuing vessel will be diflifcult' a'ndv also in a position to do the maximum damage tothe vessel below its water line. V

lt is, therefore, one ofthe objects ot the present invention to provide a device of the above general character.Y which will automatically calibrate the'mine so that it will assume a predetermined position below the surface of the water.V

A further object' is to provide an mechanism of the above general character which may be inexpensively manufactured andi assembled and appl-ied', to minesv now ot standard, equipment without material alterations or modifications.

further object is toprovide a reliable and elicient mechanism of' the above general character which may be inexpensively manufactured'- and assembled'` and' applied to :mines now of' stand-)ardL equipment without material alterations or modliications 'A further object is to provide a reiiable and etlicient mechanism of. compact construction for automatically Calibrating a minewhen launched either over. the stern of the vessel or from a submarine tube.

lVhile the invention will hereinafter be described with relation to its application tomines it is, of course, to be understood that it is applicable to other types'of floating bodies where it is desired to keep each body or member at a predetermined distance below the surface of the fluid in which it is immersed.

@ther objects will be in part obvious and inY part hereinafter pointed-'- out in connection with the accompanying sheets of' draw'- ingsillustrating one of various possible embodinients and: wherein similiar reference characters denote correspond-lingI In these drawings, Figure 1 is aL l'ongi tudinal"r sectional view of a portionL ot lthe minecase with theinventi-on applic-d thereto.

Figure 2 is a semi"-diagrainmatic view oft themine after being launchedv and,

Figure 3 is a similar view showing the mine in its final position'. i

Referring now to the drawing in detail and more particularly, Figure 1', 10 indicates the mine case which is' diagrammgatiin cally shown as spherical in shapeL although other shapes may be more desirable for use with mines adapted to be lfa-unclfied from submarines- The upper part of' the mine case is new ally provided with a .buoyancyl chamber and anl opening is formed they mine case to which the mechanism shown i-ir Figure 11 is attached.` Thisl mechanisml inclndes' gen eral cylindrical-shaped bodyv 11@ provided with anl enlarged portion 152 foi-'ming aseat for7 adiaphragm 13 hellcllv in placeby means of a coacting member 14# provided with an opening 15 leading` to the exterior` et the mine. A; longitudinally disposed tubular memberv 161 is secured to the diaphragm as shown and; provided with a valve 117 adapted-to coact with aA valve seat l@ mountedT at the endof apipe or tube 191 This valve is normally held", in restricted positiony by means of a spira-l spring 2O whereby water is permitted to flow into a collapsible chainber 21 at the end of the pipe 1'9 after entern ing the; open-ings 22 inl the capI on the outer side of the mine casing. The water is 'tree to pass through the tubular member 16 and open-ings 23"v until the press-ure on the diaphragm 13 is suilicient to force the tube 16 to close the valve 17 against its: seat 1:8 thereby to prevent a furtherv amount of water entering the collapsible chamber 21.

By reference to` Figures 2 and S it will be seen that when the mine is thrown overboard it sinks until the float 24 is partially drawn under water. This float, however, is connected by means of a line 25 with the second float 26 aswell as a line 27 leading to the mine.V After the float 24 is submerged the spring 20 which is adjusted to be compressed when the depth of the mine exceeds the length of the line 27 thus permitting the closing of the valve 17 and preventing the consequent admission of any further ballast to the tank 2l. The mine continues to sink dueto itsv slight negative buoyancy to the position shown in Figure 3 whereupon the float 26 constituting the necessary margin of safety overcomes this negative buoyancy and Vrenders the entire unit slightly buoyant thus keeping the mine at thegdesired predetermined depth below the surface.

' Itfwill thus be seen .that the present invention contemplates asimple and practical apparatus well adapted to accomplish among others all of. the objects and advantages hereinset forth. In the embodiment shown and described, twov floatsV are used but such yconstruction is not essential for'the mine case itself may be made buoyant thereby to dispense with one of these floats. In such construction, however, the large amount of line is liable'to become entangled thus somewhat reducing the reliability of the construction infactual practice.

l. In combination with a member adapted to be suspended at a predetermined depth below the surface in which it is immersed, a ballast chamber, means for admitting Vfluid to said ballast chamber and hydrostatically controlled means for stopping the admission of fluid thereto after the member has reached a predetermined depth and means including a float adapted to prevent a further sinking of said member.

2- In combination with a member adapted to be suspended at a predetermined depth below the surface in lwhich it is immersed, a ballast chamber, means for admitting the fluid lto said ballasty chamber, hydrostaticallyv controlled means for stopping the admission of fluid thereto after the member has reached a predetermined depth, means adapted to prevent ra further sinking of said member, Vsaid last mentioned means comprising two floats, one of which is adapted to retard the rdownward movement of the member and the second of which is adapted to render the entire unit slightly positively buoyant. g

3. In combination with a mine adapted i to be Vsubmerged at a predetermined depth,

a ballast tank into which seawater is permitted to flow as the mine sinks, hydrostaticallyr actuated means including aL diaphragm, a valve and valve seat for closing the admission to saidjballast tank on the mine reaching a predetermined depth and a float flexibly connected with said mine adapted to render the entire unit slightly buoyant after the valve is closed. l

4. In combination with a mine adapted to be submerged at a predetermined depth, a' [ballast tank into which sea watery is permitted to flow as the mine sinks, hydrostatically actuated means including a dia".- phragm, a valve and valve seat for closing the admission to vsaid ballast tank on the hydrostatic pressure, a valve associated with said tubular f member, a valve seat with which it coacts to close the entrance to the ballast chamber when the mine reaches a predetermined depth and means adapted to support said mine from the surfacev of the water.

` 6. In combination with a mine case having a ballast chamber, an linlet to said ballast chamberr including aY diaphragm having a tubular' member movable therewithV under hydrostatic pressure,a valvev associated with said tubular member, a valve seat Y with which it coacts to close the entrance to the ballast chamber when the mine reaches Y a predetermined depth, said means vincluding two floats, one above the other, one of which is adapted to arrest the downward movement of the minev and the other of whiehis Vadapted to `render the entire unit slightlybuoyant. Y

7 In combination witha mine adapted to be submerged to a predetermined depth, said mine being provided with a ballast tank into which sea-water is permitted to flow asthe mine sinks, hydrostatically actuated means adapted to close the admission of water to said tank when the mine reaches a predetermined depth and a float flexibly connected with the mine adapted toV keep the miner suspended at its predetermined depth. i p `Signedatlfew York, New York, this 16th day of April, 1924. v

CLARENCE VN.

HICKMANQ 

